A surface gravity traverse on Mars indicates low bedrock density at Gale crater

Science ◽  
2019 ◽  
Vol 363 (6426) ◽  
pp. 535-537 ◽  
Author(s):  
Kevin W. Lewis ◽  
Stephen Peters ◽  
Kurt Gonter ◽  
Shaunna Morrison ◽  
Nicholas Schmerr ◽  
...  

Gravimetry, the precise measurement of gravitational fields, can be used to probe the internal structure of Earth and other planets. The Curiosity rover on Mars carries accelerometers normally used for navigation and attitude determination. We have recalibrated them to isolate the signature of the changing gravitational acceleration as the rover climbs through Gale crater. The subsurface rock density is inferred from the measured decrease in gravitational field strength with elevation. The density of the sedimentary rocks in Gale crater is 1680 ± 180 kilograms per cubic meter. This value is lower than expected, indicating a high porosity and constraining maximum burial depths of the rocks over their history.

Geosphere ◽  
2020 ◽  
Vol 16 (6) ◽  
pp. 1508-1537
Author(s):  
Kenneth S. Edgett ◽  
Steven G. Banham ◽  
Kristen A. Bennett ◽  
Lauren A. Edgar ◽  
Christopher S. Edwards ◽  
...  

Abstract Extraformational sediment recycling (old sedimentary rock to new sedimentary rock) is a fundamental aspect of Earth’s geological record; tectonism exposes sedimentary rock, whereupon it is weathered and eroded to form new sediment that later becomes lithified. On Mars, tectonism has been minor, but two decades of orbiter instrument–based studies show that some sedimentary rocks previously buried to depths of kilometers have been exposed, by erosion, at the surface. Four locations in Gale crater, explored using the National Aeronautics and Space Administration’s Curiosity rover, exhibit sedimentary lithoclasts in sedimentary rock: At Marias Pass, they are mudstone fragments in sandstone derived from strata below an erosional unconformity; at Bimbe, they are pebble-sized sandstone and, possibly, laminated, intraclast-bearing, chemical (calcium sulfate) sediment fragments in conglomerates; at Cooperstown, they are pebble-sized fragments of sandstone within coarse sandstone; at Dingo Gap, they are cobble-sized, stratified sandstone fragments in conglomerate derived from an immediately underlying sandstone. Mars orbiter images show lithified sediment fans at the termini of canyons that incise sedimentary rock in Gale crater; these, too, consist of recycled, extraformational sediment. The recycled sediments in Gale crater are compositionally immature, indicating the dominance of physical weathering processes during the second known cycle. The observations at Marias Pass indicate that sediment eroded and removed from craters such as Gale crater during the Martian Hesperian Period could have been recycled to form new rock elsewhere. Our results permit prediction that lithified deltaic sediments at the Perseverance (landing in 2021) and Rosalind Franklin (landing in 2023) rover field sites could contain extraformational recycled sediment.


2017 ◽  
Vol 23 (S1) ◽  
pp. 2142-2143
Author(s):  
Kenneth S. Edgett ◽  
R. Aileen Yingst ◽  
Michelle E. Minitti ◽  
Megan R. Kennedy ◽  
Gillian M. Krezoski ◽  
...  

2017 ◽  
Author(s):  
Mathieu G.A. Lapotre ◽  
◽  
Ryan C. Ewing ◽  
Ryan C. Ewing ◽  
Michael P. Lamb ◽  
...  

Icarus ◽  
2021 ◽  
pp. 114539
Author(s):  
B.C. Johnson ◽  
R.E. Milliken ◽  
K.W. Lewis ◽  
G.S. Collins

Entropy ◽  
2021 ◽  
Vol 23 (2) ◽  
pp. 193 ◽  
Author(s):  
Giovanni Alberto Ummarino ◽  
Antonio Gallerati

We calculate the possible interaction between a superconductor and the static Earth’s gravitational fields, making use of the gravito-Maxwell formalism combined with the time-dependent Ginzburg–Landau theory. We try to estimate which are the most favorable conditions to enhance the effect, optimizing the superconductor parameters characterizing the chosen sample. We also give a qualitative comparison of the behavior of high–Tc and classical low–Tc superconductors with respect to the gravity/superfluid interplay.


2012 ◽  
Vol 27 (24) ◽  
pp. 1230023 ◽  
Author(s):  
TREVOR B. DAVIES ◽  
CHARLES H.-T. WANG ◽  
ROBERT BINGHAM ◽  
J. TITO MENDONÇA

We present a brief review on a new dynamical mechanism for a strong field effect in scalar–tensor theory. Starting with a summary of the essential features of the theory and subsequent work by several authors, we analytically investigate the parametric excitation of a scalar gravitational field in a spherically symmetric radially pulsating neutron star.


Author(s):  
Masato Akamatsu ◽  
Mitsuo Higano ◽  
Yoshio Takahashi ◽  
Hiroyuki Ozoe

Two-dimensional numerical computations were carried out for natural convection of air in a vertical cylindrical container with and without a gravitational field under a gradient of a magnetic field. The magnetic field and the magnetizing force were induced in the cylinder area and the strength and the vectors of the magnetizing force were dependent on the axial location of the electric coil. Sample computations were carried out by changing the relative orientation of an electric coil and container. In a gravitational field, air in a cylindrical container was driven by both gravitational and magnetizing forces. On the other hand, the air flow was induced by the magnetizing force even in a non-gravitational field. Flow pattern and the heat transfer rate greatly depended on the axial position of the electric coil under both gravitational and non-gravitational fields.


Eos ◽  
2022 ◽  
Vol 103 ◽  
Author(s):  
JoAnna Wendel

Period spikes of methane on Mars could originate inside Gale crater, where NASA’s Curiosity rover is currently exploring.s


Author(s):  
Tony Yuan

The relative velocity between objects with finite velocity affects the reaction between them. This effect is known as general Doppler effect. The Laser Interferometer Gravitational-Wave Observatory (LIGO) discovered gravitational waves and found their speed to be equal to the speed of light c. Gravitational waves are generated following a disturbance in the gravitational field; they affect the gravitational force on an object. Just as light waves are subject to the Doppler effect, so are gravitational waves. This article explores the following research questions concerning gravitational waves: What is the spatial distribution of gravitational waves? Can the speed of a gravitational wave represent the speed of the gravitational field (the speed of the action of the gravitational field upon the object)? What is the speed of the gravitational field? Do gravitational waves caused by the revolution of the Sun affect planetary precession? Can we modify Newton’s gravitational equation through the influence of gravitational waves?


Sign in / Sign up

Export Citation Format

Share Document